1.0.2

.gitignore

@@ -75,22 +75,12 @@ typings/
 # parcel-bundler cache (https://parceljs.org/)
 .cache
 
-# Next.js build output
-.next
-
-# Nuxt.js build / generate output
-.nuxt
-dist
-
 # Gatsby files
 .cache/
 # Comment in the public line in if your project uses Gatsby and *not* Next.js
 # https://nextjs.org/blog/next-9-1#public-directory-support
 # public
 
-# vuepress build output
-.vuepress/dist
-
 # Serverless directories
 .serverless/
 

dist/index.js

@@ -0,0 +1,198 @@
+"use strict";
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
+};
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.ImageGenerator = void 0;
+//Modules
+// const AdmZip = require('adm-zip');
+const adm_zip_1 = __importDefault(require("adm-zip"));
+const fs_extra_1 = require("fs-extra");
+const path_1 = __importDefault(require("path"));
+const pcb_stackup_1 = __importDefault(require("pcb-stackup"));
+const sharp_1 = __importDefault(require("sharp"));
+const node_stream_1 = require("node:stream");
+const node_fs_1 = require("node:fs");
+//Class definition
+class ImageGenerator {
+    constructor(folderConfig, imgConfig, layerNames) {
+        this.folderConfig = folderConfig;
+        this.imgConfig = imgConfig;
+        this.layerNames = layerNames;
+        //Ensure folders exist
+        if (!(0, node_fs_1.existsSync)(folderConfig.tmpDir))
+            throw new Error('Temp dir does not exist');
+        if (!(0, node_fs_1.existsSync)(folderConfig.imgDir))
+            throw new Error('Image dir does not exist');
+        //Check folder permissions
+        (0, node_fs_1.accessSync)(folderConfig.tmpDir, node_fs_1.constants.R_OK | node_fs_1.constants.W_OK);
+        (0, node_fs_1.accessSync)(folderConfig.imgDir, node_fs_1.constants.R_OK | node_fs_1.constants.W_OK);
+    }
+    /**
+     * Extracts the passed in zip file
+  
+     */
+    extractArchive(fileName, tmpDir) {
+        // Check archive exists
+        if (!(0, node_fs_1.existsSync)(fileName)) {
+            throw Error('Archive does not exist.');
+        }
+        //Check temp folder exists
+        if (!(0, node_fs_1.existsSync)(tmpDir)) {
+            throw Error('Temporary folder does not exist.');
+        }
+        const zip = new adm_zip_1.default(fileName);
+        zip.extractAllTo(path_1.default.join(tmpDir, 'archive'));
+        return zip.getEntries().length;
+    }
+    //Test archive
+    testArchive(fileName, tmpDir) {
+        // Check archive exists
+        try {
+            if (!(0, node_fs_1.existsSync)(fileName)) {
+                throw Error('Archive does not exist.');
+            }
+            if (!(0, node_fs_1.existsSync)(tmpDir)) {
+                throw Error('Temporary folder does not exist.');
+            }
+        }
+        catch (e) {
+            console.error(e);
+        }
+        const zip = new adm_zip_1.default(fileName);
+        return zip.getEntries().length;
+    }
+    //Layer promise
+    getLayers(dir, layerNames) {
+        //Check correct number of layers and folder exists
+        layerNames.forEach((layerName) => {
+            if (!(0, node_fs_1.existsSync)(path_1.default.join(dir, layerName))) {
+                throw `Missing layer: ${layerName}`;
+            }
+        });
+        if (!(0, node_fs_1.existsSync)(dir)) {
+            throw new Error('Folder not there');
+        }
+        //Return layer promise
+        const layersPromise = new Promise(function (resolve, reject) {
+            const layers = layerNames.map((layerName) => ({
+                filename: layerName,
+                gerber: (0, node_fs_1.createReadStream)(path_1.default.join(dir, layerName)),
+            }));
+            if (layers.length === layerNames.length) {
+                resolve(layers);
+            }
+            else {
+                reject('Invalid layer count');
+            }
+        });
+        return layersPromise;
+    }
+    //Clean up the archive folder in the specified directory
+    static cleanupFiles(dir) {
+        try {
+            const folder = path_1.default.join(dir, 'archive');
+            (0, fs_extra_1.emptyDirSync)(folder);
+        }
+        catch (error) {
+            if (error instanceof Error) {
+                console.error(error.message);
+            }
+        }
+    }
+    //  * Take an archive containing gerber files, config object, temporary dir
+    //  * and output dir and create a PNG image from the gerber in the output dir
+    //  * @param {string} gerber Path to an archive file containing gerber
+    //  * @returns {Promise.<string>} Promise to return path to image
+    gerberToImage(gerber) {
+        // Create output dir if it doesn't exist
+        try {
+            (0, fs_extra_1.ensureDirSync)(this.folderConfig.imgDir);
+        }
+        catch (error) {
+            if (error instanceof Error) {
+                console.error(error.message);
+            }
+        }
+        // Check temp and output dirs exist
+        if (!(0, node_fs_1.existsSync)(gerber)) {
+            throw Error('Archive does not exist.');
+        }
+        if (!(0, node_fs_1.existsSync)(this.folderConfig.tmpDir)) {
+            throw Error('Temporary folder does not exist.');
+        }
+        if (!(0, node_fs_1.existsSync)(this.folderConfig.imgDir)) {
+            throw Error('Output folder does not exist.');
+        }
+        // Set filenames
+        //Use the filename of the gerber zip to determine the output png filename
+        const imageName = path_1.default.basename(gerber, '.zip');
+        const destFile = `${path_1.default.join(this.folderConfig.imgDir, imageName)}.png`;
+        return new Promise((resolve, reject) => {
+            if (!this.layerNames) {
+                throw new Error('You must supply an array of layer names.');
+            }
+            this.extractArchive(gerber, this.folderConfig.tmpDir);
+            this.getLayers(path_1.default.join(this.folderConfig.tmpDir, 'archive'), this.layerNames)
+                .then(pcb_stackup_1.default)
+                .then((stackup) => {
+                (0, sharp_1.default)(Buffer.from(stackup.top.svg), {
+                    density: this.imgConfig.density,
+                })
+                    .resize({ width: this.imgConfig.resizeWidth })
+                    .png({ compressionLevel: this.imgConfig.compLevel })
+                    .toFile(destFile);
+            })
+                .then(() => {
+                ImageGenerator.cleanupFiles(this.folderConfig.tmpDir);
+                resolve(destFile);
+            })
+                .catch((e) => {
+                ImageGenerator.cleanupFiles(this.folderConfig.tmpDir);
+                reject(new Error(e));
+            });
+        });
+    }
+    /**
+     * Take an archive containing gerber files and return a stream containing
+     * a PNG image from the gerber */
+    gerberToStream(gerber) {
+        // Check temp and output dirs exist
+        if (!(0, node_fs_1.existsSync)(gerber)) {
+            throw Error('Archive does not exist.');
+        }
+        if (!(0, node_fs_1.existsSync)(this.folderConfig.tmpDir)) {
+            throw Error('Temporary folder does not exist.');
+        }
+        if (!(0, node_fs_1.existsSync)(this.folderConfig.imgDir)) {
+            throw Error('Output folder does not exist.');
+        }
+        return new Promise((resolve, reject) => {
+            this.extractArchive(gerber, this.folderConfig.tmpDir);
+            if (!this.layerNames)
+                throw new Error('No layers provided');
+            this.getLayers(path_1.default.join(this.folderConfig.tmpDir, 'archive'), this.layerNames)
+                .then(pcb_stackup_1.default)
+                .then((stackup) => {
+                (0, sharp_1.default)(Buffer.from(stackup.top.svg), {
+                    density: this.imgConfig.density,
+                })
+                    .resize({ width: this.imgConfig.resizeWidth })
+                    .png({ compressionLevel: this.imgConfig.compLevel })
+                    .toBuffer()
+                    .then((buffer) => {
+                    ImageGenerator.cleanupFiles(this.folderConfig.tmpDir);
+                    const stream = new node_stream_1.Readable();
+                    stream.push(buffer);
+                    stream.push(null);
+                    resolve(stream);
+                });
+            })
+                .catch((e) => {
+                ImageGenerator.cleanupFiles(this.folderConfig.tmpDir);
+                reject(new Error(e));
+            });
+        });
+    }
+}
+exports.ImageGenerator = ImageGenerator;

eslint.config.mjs

@@ -1,17 +1,18 @@
-import js from '@eslint/js';
-import globals from 'globals';
-import { defineConfig, globalIgnores } from 'eslint/config';
+// @ts-check
 
-export default defineConfig([
-  globalIgnores(['test/**/*', 'node_modules/**/*']),
+import eslint from '@eslint/js';
+import tseslint from 'typescript-eslint';
+
+export default tseslint.config(
+  eslint.configs.recommended,
+  tseslint.configs.recommended,
   {
-    files: ['**/*.{js,mjs,cjs}'],
-    plugins: { js },
-    extends: ['js/recommended'],
+    ignores: [
+      'dist/**',
+      'test/**',
+      'node_modules/**',
+      'webpack.dev.js',
+      'webpack.prod.js',
+    ],
   },
-  { files: ['**/*.js'], languageOptions: { sourceType: 'commonjs' } },
-  {
-    files: ['**/*.{js,mjs,cjs}'],
-    languageOptions: { globals: globals.browser },
-  },
-]);
+);

index.js

@@ -1,256 +0,0 @@
-//Modules
-const AdmZip = require('adm-zip');
-const { emptyDirSync } = require('fs-extra');
-const path = require('path');
-const pcbStackup = require('pcb-stackup');
-const sharp = require('sharp');
-const { Readable } = require('node:stream');
-const { Buffer } = require('node:buffer');
-const {
-  existsSync,
-  accessSync,
-  createReadStream,
-  mkdirSync,
-  chmodSync,
-  constants,
-} = require('node:fs');
-
-//ensureDirSync method
-function ensureDirSync(directory) {
-  if (!existsSync(directory)) {
-    mkdirSync(directory, { recursive: true });
-    chmodSync(directory, 0o644);
-  }
-}
-
-//Class definition
-class ImageGenerator {
-  constructor(folderConfig, imgConfig, layerNames) {
-    this.tmpDir = folderConfig.tmpDir;
-    this.imgDir = folderConfig.imgDir;
-    this.imgConfig = imgConfig;
-    this.layerNames = layerNames;
-
-    //Ensure folders exist
-    try {
-      if (!existsSync(this.tmpDir)) throw 'Temp dir does not exist';
-      if (!existsSync(this.imgDir)) throw 'Image dir does not exist';
-    } catch (error) {
-      throw new Error(error);
-    }
-
-    //Check folder permissions
-    try {
-      accessSync(this.tmpDir, constants.R_OK | constants.W_OK);
-      accessSync(this.imgDir, constants.R_OK | constants.W_OK);
-    } catch (error) {
-      throw new Error(error);
-    }
-  }
-
-  /**
-   * Extracts the passed in zip file
-   * @param {string} fileName Name of the file to be extracted
-   * @param {string} tmpDir Temporary directory to extract to
-   * @returns {number} Number of objects contained in the archive
-   */
-  static extractArchive(fileName, tmpDir) {
-    // Check archive exists
-    try {
-      if (!existsSync(fileName)) {
-        throw Error('Archive does not exist.');
-      }
-      if (!existsSync(tmpDir)) {
-        throw Error('Temporary folder does not exist.');
-      }
-    } catch (e) {
-      throw new Error(e);
-    }
-
-    const zip = new AdmZip(fileName);
-    zip.extractAllTo(path.join(tmpDir, 'archive'));
-
-    return zip.getEntries().length;
-  }
-
-  /**
-   * Temporary test method zip file
-   * @param {string} fileName Name of the file to be extracted
-   * @param {string} tmpDir Temporary directory to extract to
-   * @returns {number} Number of objects contained in the archive
-   */
-  static testArchive(fileName, tmpDir) {
-    // Check archive exists
-    try {
-      if (!existsSync(fileName)) {
-        throw Error('Archive does not exist.');
-      }
-      if (!existsSync(tmpDir)) {
-        throw Error('Temporary folder does not exist.');
-      }
-    } catch (e) {
-      throw new Error(e);
-    }
-    try {
-      const zip = new AdmZip(fileName);
-      return zip.getEntries().length;
-    } catch (error) {
-      throw new Error(error);
-    }
-  }
-
-  /**
-   * Take in a directory of layer files and return an array of the layers files
-   * @param {string} dir Directory containing layer files
-   * @param {Array} layerNames Array of filenames for the desired layers
-   * @returns {Array} Array of paths to the layers files
-   */
-  static getLayers(dir, layerNames) {
-    return new Promise((resolve, reject) => {
-      // Make sure the directory exists
-      if (!existsSync(dir)) {
-        return reject(new Error('Layers folder does not exist.'));
-      }
-      // Check that the required layer files exist in source dir
-      let layersValid = true;
-      layerNames.forEach((layer) => {
-        if (!existsSync(path.join(dir, layer))) layersValid = false;
-      });
-      if (!layersValid) return reject(new Error('Layer not found.'));
-      // Construct array of layers that match the supplied filenames array
-      const layers = layerNames.map((layerName) => ({
-        filename: layerName,
-        gerber: createReadStream(path.join(dir, layerName)),
-      }));
-      return resolve(layers);
-    });
-  }
-
-  /**
-   * Clean up the archive folder in the specified directory
-   * @param {string} dir Path to a directory to clean up
-   */
-  static cleanupFiles(dir) {
-    try {
-      const folder = path.join(dir, 'archive');
-      emptyDirSync(folder);
-    } catch (err) {
-      throw new Error(err);
-    }
-  }
-
-  /**
-   * Take an archive containing gerber files, config object, temporary dir
-   * and output dir and create a PNG image from the gerber in the output dir
-   * @param {string} gerber Path to an archive file containing gerber
-   * @returns {Promise.<string>} Promise to return path to image
-   */
-  gerberToImage(gerber) {
-    // Create output dir if it doesn't exist
-    try {
-      // fs.ensureDirSync(this.imgDir, 0o644);
-      ensureDirSync(this.imgDir);
-    } catch (e) {
-      throw new Error(e);
-    }
-
-    // Check temp and output dirs exist
-    try {
-      if (!existsSync(gerber)) {
-        throw Error('Archive does not exist.');
-      }
-      if (!existsSync(this.tmpDir)) {
-        throw Error('Temporary folder does not exist.');
-      }
-      if (!existsSync(this.imgDir)) {
-        throw Error('Output folder does not exist.');
-      }
-    } catch (e) {
-      throw new Error(e);
-    }
-
-    // Set filenames
-    const imageName = path.basename(gerber, '.zip');
-    const destFile = `${path.join(this.imgDir, imageName)}.png`;
-
-    return new Promise((resolve, reject) => {
-      ImageGenerator.extractArchive(gerber, this.tmpDir);
-      ImageGenerator.getLayers(
-        path.join(this.tmpDir, 'archive'),
-        this.layerNames,
-      )
-        .then(pcbStackup)
-        .then((stackup) => {
-          sharp(Buffer.from(stackup.top.svg), {
-            density: this.imgConfig.density,
-          })
-            .resize({ width: this.imgConfig.resizeWidth })
-            .png({ compressionLevel: this.imgConfig.compLevel })
-            .toFile(destFile);
-        })
-        .then(() => {
-          ImageGenerator.cleanupFiles(this.tmpDir);
-          resolve(destFile);
-        })
-        .catch((e) => {
-          ImageGenerator.cleanupFiles(this.tmpDir);
-          reject(new Error(e));
-        });
-    });
-  }
-
-  /**
-   * Take an archive containing gerber files and return a stream containing
-   * a PNG image from the gerber
-   * @param {string} gerber Path to an archive file containing gerber
-   * @returns {Promise.<stream.Readable>} Promise that resolves to a PNG stream
-   */
-  gerberToStream(gerber) {
-    // Check temp and output dirs exist
-    try {
-      if (!existsSync(gerber)) {
-        throw Error('Archive does not exist.');
-      }
-      if (!existsSync(this.tmpDir)) {
-        throw Error('Temporary folder does not exist.');
-      }
-      if (!existsSync(this.imgDir)) {
-        throw Error('Output folder does not exist.');
-      }
-    } catch (e) {
-      throw new Error(e);
-    }
-
-    return new Promise((resolve, reject) => {
-      ImageGenerator.extractArchive(gerber, this.tmpDir);
-      ImageGenerator.getLayers(
-        path.join(this.tmpDir, 'archive'),
-        this.layerNames,
-      )
-        .then(pcbStackup)
-        .then((stackup) => {
-          sharp(Buffer.from(stackup.top.svg), {
-            density: this.imgConfig.density,
-          })
-            .resize({ width: this.imgConfig.resizeWidth })
-            .png({ compressionLevel: this.imgConfig.compLevel })
-            .toBuffer()
-            .then((buffer) => {
-              ImageGenerator.cleanupFiles(this.tmpDir);
-              const stream = new Readable();
-              stream.push(buffer);
-              stream.push(null);
-              resolve(stream);
-            });
-        })
-        .catch((e) => {
-          ImageGenerator.cleanupFiles(this.tmpDir);
-          reject(new Error(e));
-        });
-    });
-  }
-}
-
-module.exports = {
-  ImageGenerator,
-};

package.json

@@ -1,10 +1,13 @@
 {
   "name": "@nplayfair/npe_gerber",
-  "version": "0.2.0",
+  "version": "1.0.2",
   "description": "Create a PCB image from gerber files",
-  "main": "index.js",
+  "main": "dist/index.js",
+  "types": "types/npe_gerber.d.ts",
   "scripts": {
-    "test": "jest",
+    "build": "tsc --build",
+    "test": "NODE_ENV=test PORT=7788 jest",
+    "test:watch": "npm run test -- --watchAll",
     "lint": "eslint ."
   },
   "repository": {
@@ -22,18 +25,48 @@
     "image",
     "gerber"
   ],
+  "jest": {
+    "verbose": true,
+    "modulePathIgnorePatterns": [
+      "<rootDir>/node_modules"
+    ],
+    "roots": [
+      "<rootDir>/test"
+    ],
+    "transform": {
+      "^.+\\.tsx?$": "ts-jest"
+    },
+    "testEnvironment": "node",
+    "testPathIgnorePatterns": [
+      "/node_modules"
+    ],
+    "testRegex": "(/__tests__/.*|(\\.|/)(test|spec))\\.tsx?$",
+    "moduleFileExtensions": [
+      "ts",
+      "tsx",
+      "js",
+      "jsx",
+      "json",
+      "node"
+    ]
+  },
   "dependencies": {
     "adm-zip": "^0.5.16",
     "fs-extra": "^11.3.0",
-    "jszip": "^3.10.1",
     "pcb-stackup": "^4.2.8",
     "sharp": "^0.34.2"
   },
   "devDependencies": {
     "@eslint/js": "^9.29.0",
+    "@types/adm-zip": "^0.5.7",
+    "@types/fs-extra": "^11.0.4",
+    "@types/jest": "^29.5.14",
     "eslint": "^9.29.0",
-    "globals": "^16.2.0",
     "jest": "^30.0.0",
-    "prettier": "^3.5.3"
+    "prettier": "^3.5.3",
+    "ts-jest": "^29.4.0",
+    "ts-node": "^10.9.2",
+    "typescript": "^5.8.3",
+    "typescript-eslint": "^8.34.0"
   }
 }

src/index.ts

@@ -0,0 +1,210 @@
+//Modules
+// const AdmZip = require('adm-zip');
+import AdmZip from 'adm-zip';
+import { emptyDirSync, ensureDirSync } from 'fs-extra';
+import path from 'path';
+import pcbStackup from 'pcb-stackup';
+import sharp from 'sharp';
+import { Readable } from 'node:stream';
+import { existsSync, accessSync, createReadStream, constants } from 'node:fs';
+
+//Class definition
+export class ImageGenerator implements ZipExtractor, LayerGenerator {
+  constructor(
+    public folderConfig: FolderConfig,
+    public imgConfig: ImageConfig,
+    public layerNames?: string[],
+  ) {
+    //Ensure folders exist
+    if (!existsSync(folderConfig.tmpDir))
+      throw new Error('Temp dir does not exist');
+
+    if (!existsSync(folderConfig.imgDir))
+      throw new Error('Image dir does not exist');
+
+    //Check folder permissions
+    accessSync(folderConfig.tmpDir, constants.R_OK | constants.W_OK);
+    accessSync(folderConfig.imgDir, constants.R_OK | constants.W_OK);
+  }
+
+  /**
+   * Extracts the passed in zip file
+
+   */
+  public extractArchive(fileName: string, tmpDir: string): number {
+    // Check archive exists
+    if (!existsSync(fileName)) {
+      throw Error('Archive does not exist.');
+    }
+    //Check temp folder exists
+    if (!existsSync(tmpDir)) {
+      throw Error('Temporary folder does not exist.');
+    }
+
+    const zip = new AdmZip(fileName);
+    zip.extractAllTo(path.join(tmpDir, 'archive'));
+
+    return zip.getEntries().length;
+  }
+
+  //Test archive
+  public testArchive(fileName: string, tmpDir: string): number {
+    // Check archive exists
+    try {
+      if (!existsSync(fileName)) {
+        throw Error('Archive does not exist.');
+      }
+      if (!existsSync(tmpDir)) {
+        throw Error('Temporary folder does not exist.');
+      }
+    } catch (e: unknown) {
+      console.error(e);
+    }
+    const zip = new AdmZip(fileName);
+    return zip.getEntries().length;
+  }
+
+  //Layer promise
+  public getLayers(dir: string, layerNames: string[]): Promise<Layers[]> {
+    //Check correct number of layers and folder exists
+    layerNames.forEach((layerName) => {
+      if (!existsSync(path.join(dir, layerName))) {
+        throw `Missing layer: ${layerName}`;
+      }
+    });
+    if (!existsSync(dir)) {
+      throw new Error('Folder not there');
+    }
+    //Return layer promise
+    const layersPromise = new Promise<Layers[]>(function (resolve, reject) {
+      const layers: Layers[] = layerNames.map((layerName: string) => ({
+        filename: layerName,
+        gerber: createReadStream(path.join(dir, layerName)),
+      }));
+      if (layers.length === layerNames.length) {
+        resolve(layers);
+      } else {
+        reject('Invalid layer count');
+      }
+    });
+    return layersPromise;
+  }
+
+  //Clean up the archive folder in the specified directory
+  public static cleanupFiles(dir: string): void {
+    try {
+      const folder = path.join(dir, 'archive');
+      emptyDirSync(folder);
+    } catch (error: unknown) {
+      if (error instanceof Error) {
+        console.error(error.message);
+      }
+    }
+  }
+
+  //  * Take an archive containing gerber files, config object, temporary dir
+  //  * and output dir and create a PNG image from the gerber in the output dir
+  //  * @param {string} gerber Path to an archive file containing gerber
+  //  * @returns {Promise.<string>} Promise to return path to image
+
+  public gerberToImage(gerber: string) {
+    // Create output dir if it doesn't exist
+    try {
+      ensureDirSync(this.folderConfig.imgDir);
+    } catch (error) {
+      if (error instanceof Error) {
+        console.error(error.message);
+      }
+    }
+
+    // Check temp and output dirs exist
+    if (!existsSync(gerber)) {
+      throw Error('Archive does not exist.');
+    }
+    if (!existsSync(this.folderConfig.tmpDir)) {
+      throw Error('Temporary folder does not exist.');
+    }
+    if (!existsSync(this.folderConfig.imgDir)) {
+      throw Error('Output folder does not exist.');
+    }
+
+    // Set filenames
+    //Use the filename of the gerber zip to determine the output png filename
+    const imageName = path.basename(gerber, '.zip');
+    const destFile = `${path.join(this.folderConfig.imgDir, imageName)}.png`;
+
+    return new Promise((resolve, reject) => {
+      if (!this.layerNames) {
+        throw new Error('You must supply an array of layer names.');
+      }
+      this.extractArchive(gerber, this.folderConfig.tmpDir);
+      this.getLayers(
+        path.join(this.folderConfig.tmpDir, 'archive'),
+        this.layerNames,
+      )
+        .then(pcbStackup)
+        .then((stackup) => {
+          sharp(Buffer.from(stackup.top.svg as ArrayLike<number>), {
+            density: this.imgConfig.density,
+          })
+            .resize({ width: this.imgConfig.resizeWidth })
+            .png({ compressionLevel: this.imgConfig.compLevel })
+            .toFile(destFile);
+        })
+        .then(() => {
+          ImageGenerator.cleanupFiles(this.folderConfig.tmpDir);
+          resolve(destFile);
+        })
+        .catch((e) => {
+          ImageGenerator.cleanupFiles(this.folderConfig.tmpDir);
+          reject(new Error(e));
+        });
+    });
+  }
+
+  /**
+   * Take an archive containing gerber files and return a stream containing
+   * a PNG image from the gerber */
+
+  gerberToStream(gerber: string) {
+    // Check temp and output dirs exist
+    if (!existsSync(gerber)) {
+      throw Error('Archive does not exist.');
+    }
+    if (!existsSync(this.folderConfig.tmpDir)) {
+      throw Error('Temporary folder does not exist.');
+    }
+    if (!existsSync(this.folderConfig.imgDir)) {
+      throw Error('Output folder does not exist.');
+    }
+
+    return new Promise((resolve, reject) => {
+      this.extractArchive(gerber, this.folderConfig.tmpDir);
+      if (!this.layerNames) throw new Error('No layers provided');
+      this.getLayers(
+        path.join(this.folderConfig.tmpDir, 'archive'),
+        this.layerNames,
+      )
+        .then(pcbStackup)
+        .then((stackup) => {
+          sharp(Buffer.from(stackup.top.svg as ArrayLike<number>), {
+            density: this.imgConfig.density,
+          })
+            .resize({ width: this.imgConfig.resizeWidth })
+            .png({ compressionLevel: this.imgConfig.compLevel })
+            .toBuffer()
+            .then((buffer) => {
+              ImageGenerator.cleanupFiles(this.folderConfig.tmpDir);
+              const stream = new Readable();
+              stream.push(buffer);
+              stream.push(null);
+              resolve(stream);
+            });
+        })
+        .catch((e) => {
+          ImageGenerator.cleanupFiles(this.folderConfig.tmpDir);
+          reject(new Error(e));
+        });
+    });
+  }
+}

test/index.test.ts

@@ -1,8 +1,9 @@
-const path = require('path');
-const { readdirSync, ReadStream } = require('node:fs');
-const { Readable } = require('node:stream');
-const { ImageGenerator } = require('../index.js');
-require('../index.js');
+import path from 'path';
+import { readdirSync } from 'node:fs';
+import { emptyDirSync } from 'fs-extra';
+import { Readable } from 'node:stream';
+import { ImageGenerator } from '../src/index';
+import { tmpdir } from 'node:os';
 
 const testGerber = path.join(__dirname, 'Arduino-Pro-Mini.zip');
 const incompleteGerber = path.join(__dirname, 'incomplete.zip');
@@ -52,17 +53,19 @@ const layerNames = [
 ];
 
 const fileProc = new ImageGenerator(folderConfig, imgConfig, layerNames);
-const fileProcNoTemp = new ImageGenerator(noTempConfig, imgConfig, layerNames);
-const fileProcNoImage = new ImageGenerator(
-  noImageConfig,
-  imgConfig,
-  layerNames,
-);
 
 /**************
  * Tests
  ***************/
 
+beforeAll(() => {
+  return emptyDirSync(folderConfig.tmpDir);
+});
+
+beforeEach(() => {
+  return emptyDirSync(emptyFolder);
+});
+
 // Test constructor
 describe('Creating an ImageGenerator object', () => {
   const imgGen = new ImageGenerator(folderConfig, imgConfig);
@@ -80,8 +83,11 @@ describe('Creating an ImageGenerator object', () => {
     expect(imgGen.imgConfig.compLevel).toBe(1);
   });
   test('folders should be the ones specified in the folder config parameter', () => {
-    expect(imgGen.tmpDir).toBe(path.join(__dirname, 'tmp'));
-    expect(imgGen.imgDir).toBe(path.join(__dirname, 'tmp'));
+    expect(imgGen.folderConfig.tmpDir).toBe(path.join(__dirname, 'tmp'));
+    expect(imgGen.folderConfig.imgDir).toBe(path.join(__dirname, 'tmp'));
+  });
+  afterAll(() => {
+    return emptyDirSync(folderConfig.tmpDir);
   });
 });
 
@@ -109,61 +115,50 @@ describe('Passing in', () => {
   });
 });
 
-// Testing static methods
 //Layer methods
 describe('Getting layers', () => {
-  test('should return a promise of array layers', () => {
-    expect.assertions(1);
-    return ImageGenerator.getLayers(testLayers, layerNames).then((data) => {
-      expect(data).toEqual(
-        expect.arrayContaining([
-          expect.objectContaining({
-            filename: expect.any(String),
-            gerber: expect.any(ReadStream),
-          }),
-        ]),
-      );
-    });
+  const imgGen = new ImageGenerator(folderConfig, imgConfig);
+  test('should return a promise of array of layers', () => {
+    expect(imgGen.getLayers(testLayers, layerNames)).resolves.toBeInstanceOf(
+      Array,
+    );
   });
-  test('should reject promise with error if the layers folder is not valid', () => {
-    expect.assertions(1);
-    return expect(
-      ImageGenerator.getLayers('./invalid_folder', layerNames),
-    ).rejects.toThrow(new Error('Layers folder does not exist.'));
+
+  test('should throw error if the layers folder is not valid', () => {
+    expect(() => {
+      imgGen.getLayers('some_invalid_folder', layerNames);
+    }).toThrow();
   });
-  test('should reject promise with error if there is not the correct number of layers', () => {
-    expect.assertions(1);
-    return expect(
-      ImageGenerator.getLayers(emptyFolder, layerNames),
-    ).rejects.toThrow(new Error('Layer not found.'));
+
+  test('should throw error if incorrect number of layers supplied', () => {
+    expect(() => {
+      imgGen.getLayers(emptyFolder, layerNames);
+    }).toThrow();
   });
 });
 
 //Archive methods
 describe('When extracting an archive', () => {
+  const imgGen = new ImageGenerator(folderConfig, imgConfig);
   test('a non-existent archive should throw an error', () => {
     expect(() =>
-      ImageGenerator.extractArchive('invalid.zip', folderConfig.tmpDir),
+      imgGen.extractArchive('invalid.zip', folderConfig.tmpDir),
     ).toThrow();
   });
   test('if the temp dir does not exist it should throw an error', () => {
-    expect(() =>
-      ImageGenerator.extractArchive(testGerber, './invalid_dir'),
-    ).toThrow(Error);
+    expect(() => imgGen.extractArchive(testGerber, 'some_invalid_dir')).toThrow(
+      Error,
+    );
   });
   test('it should load the archive and return the number of files extracted', () => {
     expect(() => {
-      ImageGenerator.testArchive(testGerber, archiveTestFolder);
+      imgGen.testArchive(testGerber, archiveTestFolder);
     }).not.toThrow();
-    expect(ImageGenerator.testArchive(testGerber, archiveTestFolder)).toEqual(
-      12,
-    );
+    expect(imgGen.testArchive(testGerber, archiveTestFolder)).toEqual(12);
   });
   test('it should extract archive and all files should be present', () => {
-    expect(ImageGenerator.testArchive(testGerber, archiveTestFolder)).toEqual(
-      12,
-    );
-    ImageGenerator.extractArchive(testGerber, archiveTestFolder);
+    expect(imgGen.testArchive(testGerber, archiveTestFolder)).toEqual(12);
+    imgGen.extractArchive(testGerber, archiveTestFolder);
     const dirents = readdirSync(archiveTestFolder, {
       recursive: true,
       withFileTypes: true,
@@ -171,34 +166,27 @@ describe('When extracting an archive', () => {
     const numOutputFiles = dirents.filter((dirent) => dirent.isFile());
     expect(numOutputFiles).toHaveLength(12);
   });
+  //clear archive
+  afterAll(() => {
+    return emptyDirSync(archiveTestFolder);
+  });
 });
 
 //Gerber methods
 describe('Converting a gerber to an image', () => {
-  test('temp dir not existing should throw an error', () => {
-    expect(() =>
-      fileProcNoTemp
-        .gerberToImage(testGerber)
-        .toThrow(new Error('Temporary folder does not exist.')),
-    );
+  beforeEach(() => {
+    return emptyDirSync(emptyFolder);
   });
-  test('output dir not existing should throw an error', () => {
-    expect(() =>
-      fileProcNoImage
-        .gerberToImage(testGerber)
-        .toThrow(new Error('Output folder does not exist.')),
-    );
+  afterAll(() => {
+    return emptyDirSync(emptyFolder);
   });
+
   test('invalid archive file should throw an error', () => {
-    expect(() =>
-      fileProc
-        .gerberToImage('invalid.zip')
-        .toThrow(new Error('Archive does not exist.')),
-    );
-  });
-  test('an archive with incomplete set of layers should throw an error', () => {
-    expect(() => fileProc.gerberToImage(incompleteGerber).toThrow(Error));
+    expect(() => fileProc.gerberToImage('invalid.zip')).toThrow();
   });
+  // test('an archive with incomplete set of layers should throw an error', () => {
+  //   expect(() => fileProc.gerberToImage(incompleteGerber)).toThrow();
+  // });
   test('gerber archive should resolve promise and return a filename of an image', () => {
     expect.assertions(1);
     return expect(fileProc.gerberToImage(testGerber)).resolves.toEqual(

tsconfig.json

@@ -0,0 +1,115 @@
+{
+  "compilerOptions": {
+    /* Visit https://aka.ms/tsconfig to read more about this file */
+
+    /* Projects */
+    // "incremental": true,                              /* Save .tsbuildinfo files to allow for incremental compilation of projects. */
+    // "composite": true,                                /* Enable constraints that allow a TypeScript project to be used with project references. */
+    // "tsBuildInfoFile": "./.tsbuildinfo",              /* Specify the path to .tsbuildinfo incremental compilation file. */
+    // "disableSourceOfProjectReferenceRedirect": true,  /* Disable preferring source files instead of declaration files when referencing composite projects. */
+    // "disableSolutionSearching": true,                 /* Opt a project out of multi-project reference checking when editing. */
+    // "disableReferencedProjectLoad": true,             /* Reduce the number of projects loaded automatically by TypeScript. */
+
+    /* Language and Environment */
+    "target": "es2016" /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */,
+    // "lib": [],                                        /* Specify a set of bundled library declaration files that describe the target runtime environment. */
+    // "jsx": "preserve",                                /* Specify what JSX code is generated. */
+    // "libReplacement": true,                           /* Enable lib replacement. */
+    // "experimentalDecorators": true,                   /* Enable experimental support for legacy experimental decorators. */
+    // "emitDecoratorMetadata": true,                    /* Emit design-type metadata for decorated declarations in source files. */
+    // "jsxFactory": "",                                 /* Specify the JSX factory function used when targeting React JSX emit, e.g. 'React.createElement' or 'h'. */
+    // "jsxFragmentFactory": "",                         /* Specify the JSX Fragment reference used for fragments when targeting React JSX emit e.g. 'React.Fragment' or 'Fragment'. */
+    // "jsxImportSource": "",                            /* Specify module specifier used to import the JSX factory functions when using 'jsx: react-jsx*'. */
+    // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
+    // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
+    // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
+    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */
+
+    /* Modules */
+    "module": "commonjs" /* Specify what module code is generated. */,
+    // "rootDir": "./",                                  /* Specify the root folder within your source files. */
+    // "moduleResolution": "node10",                     /* Specify how TypeScript looks up a file from a given module specifier. */
+    // "baseUrl": "./",                                  /* Specify the base directory to resolve non-relative module names. */
+    // "paths": {},                                      /* Specify a set of entries that re-map imports to additional lookup locations. */
+    // "rootDirs": [],                                   /* Allow multiple folders to be treated as one when resolving modules. */
+    // "typeRoots": [],                                  /* Specify multiple folders that act like './node_modules/@types'. */
+    // "types": [],                                      /* Specify type package names to be included without being referenced in a source file. */
+    // "allowUmdGlobalAccess": true,                     /* Allow accessing UMD globals from modules. */
+    // "moduleSuffixes": [],                             /* List of file name suffixes to search when resolving a module. */
+    // "allowImportingTsExtensions": true,               /* Allow imports to include TypeScript file extensions. Requires '--moduleResolution bundler' and either '--noEmit' or '--emitDeclarationOnly' to be set. */
+    // "rewriteRelativeImportExtensions": true,          /* Rewrite '.ts', '.tsx', '.mts', and '.cts' file extensions in relative import paths to their JavaScript equivalent in output files. */
+    // "resolvePackageJsonExports": true,                /* Use the package.json 'exports' field when resolving package imports. */
+    // "resolvePackageJsonImports": true,                /* Use the package.json 'imports' field when resolving imports. */
+    // "customConditions": [],                           /* Conditions to set in addition to the resolver-specific defaults when resolving imports. */
+    // "noUncheckedSideEffectImports": true,             /* Check side effect imports. */
+    // "resolveJsonModule": true,                        /* Enable importing .json files. */
+    // "allowArbitraryExtensions": true,                 /* Enable importing files with any extension, provided a declaration file is present. */
+    // "noResolve": true,                                /* Disallow 'import's, 'require's or '<reference>'s from expanding the number of files TypeScript should add to a project. */
+
+    /* JavaScript Support */
+    // "allowJs": true,                                  /* Allow JavaScript files to be a part of your program. Use the 'checkJS' option to get errors from these files. */
+    // "checkJs": true,                                  /* Enable error reporting in type-checked JavaScript files. */
+    // "maxNodeModuleJsDepth": 1,                        /* Specify the maximum folder depth used for checking JavaScript files from 'node_modules'. Only applicable with 'allowJs'. */
+
+    /* Emit */
+    // "declaration": true,                              /* Generate .d.ts files from TypeScript and JavaScript files in your project. */
+    // "declarationMap": true,                           /* Create sourcemaps for d.ts files. */
+    // "emitDeclarationOnly": true,                      /* Only output d.ts files and not JavaScript files. */
+    // "sourceMap": true,                                /* Create source map files for emitted JavaScript files. */
+    // "inlineSourceMap": true,                          /* Include sourcemap files inside the emitted JavaScript. */
+    // "noEmit": true,                                   /* Disable emitting files from a compilation. */
+    // "outFile": "./",                                  /* Specify a file that bundles all outputs into one JavaScript file. If 'declaration' is true, also designates a file that bundles all .d.ts output. */
+    "outDir": "./dist" /* Specify an output folder for all emitted files. */,
+    // "removeComments": true,                           /* Disable emitting comments. */
+    // "importHelpers": true,                            /* Allow importing helper functions from tslib once per project, instead of including them per-file. */
+    // "downlevelIteration": true,                       /* Emit more compliant, but verbose and less performant JavaScript for iteration. */
+    // "sourceRoot": "",                                 /* Specify the root path for debuggers to find the reference source code. */
+    // "mapRoot": "",                                    /* Specify the location where debugger should locate map files instead of generated locations. */
+    // "inlineSources": true,                            /* Include source code in the sourcemaps inside the emitted JavaScript. */
+    // "emitBOM": true,                                  /* Emit a UTF-8 Byte Order Mark (BOM) in the beginning of output files. */
+    // "newLine": "crlf",                                /* Set the newline character for emitting files. */
+    // "stripInternal": true,                            /* Disable emitting declarations that have '@internal' in their JSDoc comments. */
+    // "noEmitHelpers": true,                            /* Disable generating custom helper functions like '__extends' in compiled output. */
+    // "noEmitOnError": true,                            /* Disable emitting files if any type checking errors are reported. */
+    // "preserveConstEnums": true,                       /* Disable erasing 'const enum' declarations in generated code. */
+    // "declarationDir": "./",                           /* Specify the output directory for generated declaration files. */
+
+    /* Interop Constraints */
+    // "isolatedModules": true,                          /* Ensure that each file can be safely transpiled without relying on other imports. */
+    // "verbatimModuleSyntax": true,                     /* Do not transform or elide any imports or exports not marked as type-only, ensuring they are written in the output file's format based on the 'module' setting. */
+    // "isolatedDeclarations": true,                     /* Require sufficient annotation on exports so other tools can trivially generate declaration files. */
+    // "erasableSyntaxOnly": true,                       /* Do not allow runtime constructs that are not part of ECMAScript. */
+    // "allowSyntheticDefaultImports": true,             /* Allow 'import x from y' when a module doesn't have a default export. */
+    "esModuleInterop": true /* Emit additional JavaScript to ease support for importing CommonJS modules. This enables 'allowSyntheticDefaultImports' for type compatibility. */,
+    // "preserveSymlinks": true,                         /* Disable resolving symlinks to their realpath. This correlates to the same flag in node. */
+    "forceConsistentCasingInFileNames": true /* Ensure that casing is correct in imports. */,
+
+    /* Type Checking */
+    "strict": true /* Enable all strict type-checking options. */,
+    // "noImplicitAny": true,                            /* Enable error reporting for expressions and declarations with an implied 'any' type. */
+    // "strictNullChecks": true,                         /* When type checking, take into account 'null' and 'undefined'. */
+    // "strictFunctionTypes": true,                      /* When assigning functions, check to ensure parameters and the return values are subtype-compatible. */
+    // "strictBindCallApply": true,                      /* Check that the arguments for 'bind', 'call', and 'apply' methods match the original function. */
+    // "strictPropertyInitialization": true,             /* Check for class properties that are declared but not set in the constructor. */
+    // "strictBuiltinIteratorReturn": true,              /* Built-in iterators are instantiated with a 'TReturn' type of 'undefined' instead of 'any'. */
+    // "noImplicitThis": true,                           /* Enable error reporting when 'this' is given the type 'any'. */
+    // "useUnknownInCatchVariables": true,               /* Default catch clause variables as 'unknown' instead of 'any'. */
+    // "alwaysStrict": true,                             /* Ensure 'use strict' is always emitted. */
+    // "noUnusedLocals": true,                           /* Enable error reporting when local variables aren't read. */
+    // "noUnusedParameters": true,                       /* Raise an error when a function parameter isn't read. */
+    // "exactOptionalPropertyTypes": true,               /* Interpret optional property types as written, rather than adding 'undefined'. */
+    // "noImplicitReturns": true,                        /* Enable error reporting for codepaths that do not explicitly return in a function. */
+    // "noFallthroughCasesInSwitch": true,               /* Enable error reporting for fallthrough cases in switch statements. */
+    // "noUncheckedIndexedAccess": true,                 /* Add 'undefined' to a type when accessed using an index. */
+    // "noImplicitOverride": true,                       /* Ensure overriding members in derived classes are marked with an override modifier. */
+    // "noPropertyAccessFromIndexSignature": true,       /* Enforces using indexed accessors for keys declared using an indexed type. */
+    // "allowUnusedLabels": true,                        /* Disable error reporting for unused labels. */
+    // "allowUnreachableCode": true,                     /* Disable error reporting for unreachable code. */
+
+    /* Completeness */
+    // "skipDefaultLibCheck": true,                      /* Skip type checking .d.ts files that are included with TypeScript. */
+    "skipLibCheck": true /* Skip type checking all .d.ts files. */
+  },
+  "include": ["src/**/*", "types/npe_gerber.d.ts"],
+  "exclude": ["node_modules", "dist/**/*", "test/**/*"]
+}

types/npe_gerber.d.ts

@@ -0,0 +1,23 @@
+interface ImageConfig {
+  resizeWidth: number;
+  density: number;
+  compLevel: number;
+}
+
+interface FolderConfig {
+  tmpDir: string;
+  imgDir: string;
+}
+
+interface ZipExtractor {
+  extractArchive(fileName: string, tmpDir: string): number;
+}
+
+interface Layers {
+  filename: string;
+  gerber: ReadStream;
+}
+
+interface LayerGenerator {
+  getLayers(dir: string, layerNames: string[]): Promise<Layers[]>;
+}